Concept ObjectTransform

ObjectTransform

Description

An ObjectTransform is a function type or a function
pointer type where the return type Obj is a
an object type and the arguments are
Transforms. is_callable< Obj >::value
must be false. The ObjectTransform, when applied,
has the effect of constructing an object of type
Obj' (see below), passing as construction parameters
the result(s) of applying transform(s) Tn.

The type Obj may be a template specialization representing
a compile-time lambda expression. For instance, if Obj is
std::pair< proto::_value, int >, the result type of the
ObjectTransform is computed by replacing the type proto::_value
with the result of applying the proto::_value transform. For
given types Obj, Expr, State and Data, we can say that the
type Obj' represents the type Obj after all nested transforms
have been replaced with the results of applying the transforms
with Expr, State and Data as transform arguments.

If the type Obj is not a template specialization representing
a compile-time lambda expression, then the result type Obj' is
the same as Obj.